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Flashcards in Bacteria Structure Deck (20)
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1
Q

What is the shape of the Vibrio Cholera?

A

Spiral shaped.

2
Q

What is the shape of Strep?

A

Chains of Spheres

3
Q

What is the shape of Staph?

A

Grape-like Clusters (Spheres)

4
Q

Difference between gram positive and negative?

A
Positive = Thick Peptidoglycan Layer
Negative = Thin Peptidoglycan layer with an outer membrane
5
Q

What are the steps in Gram Stain?

A
  1. Crystal Violet = stains purple
  2. Gram’s Iodine
  3. Alcohol - removes stain from gram negative due to porins allowing the purple to be removed
  4. Safarin Red - dyes the colorless microbes red/pink and if purple will stay purpse
    Gram Positive = Purple
    Gram Negative = Pink
6
Q

Gram Positive cell wall characteristics?

A

Thick Peptidoglycan and Teichonic Acid

7
Q

Gram Negative cell wall characteristics?

A

Thin Peptidoglycan
Outer Membrane
- Lipopolysacchrides
- Porins

8
Q

What kind of bacteria can have a capsule?

A

Both kinds of bacteria can have a capsule. The capsule would be outside of the other membranes.

9
Q

Which kind of bacterium have more cross-linking of peptidoglycan?

A

Gram Positive

10
Q

What unique structure is used on gram positive outer membrane for Toll-Like Receptor recognition?

A

Teichonic Acid

11
Q

What are the parts of LPS and what kind of bacteria?

A

Gram Negative Only. Recognized by innate immune system.
Most Outer level is variable the O-Antigen (recognized)
Lipid A at the base, induces fever/endotoxin

12
Q

What are the PAMPs of both gram positive and negative bacteria?

A
Positive = Lipoteichonic Acid
Negative = Lipopolysaccharide
13
Q

What are the function of fimbriae and pili?

A

Adherence to cells and are virulence determinants. Unique to come types of bacteria.

14
Q

What are the differences between flagella of enteric bacteria and pseudomonads?

A

Pseudomonads - single polar flagella

Enteric - multiple flagella over the cell

15
Q

What do the types of secretions mechanisms do?

A

Type II - secrete protein
Type III - delivers toxins
Type IV - delivers DNA
–virulence factors–

16
Q

How does having a capsule benefit the bacterium?

A

Can prevent the bacteria from getting phagocytosed and can hide the antigens.

17
Q

What is the primary virulence factor of Haemophilus and where does it infect?

A

Type B Polysaccharide Capsule and primary infection site is usually the nasopharynx

18
Q

Who does Haemophilus primarily effect and what does it cause?

A

Highest incidence of Meningitis in 3 month to 2 year olds.

3 months because that’s after Ab protection from mother wears off

19
Q

Why are capsules poor immunogens?

A

Due to the repetitive sequence unable to elicit a strong immune response.

20
Q

What is a conjugate vaccine and how did they use it for Haemophilus?

A

Conjugate vaccine is when they pair another antigen with the capsule antigen to elicit a strong response to get a T-cell dependent response.